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21.
再生障碍性贫血不同地区、不同学者的不同治疗方法,反映了人们对疾病的不同的认识,主流意见一是从肾辨证立论,二是综合脏腑、阴阳、气血、病因辨证用药.急慢性再障病理特点和临床表现的不同是中医辨证治疗的基础.治用四联生血汤补肾益肾,健脾资料,清热解毒,活血化瘀.  相似文献   
22.
A Zn(Cys)(4) center has been found in the C-terminal region of the crystal structure of the anaerobic class III ribonucleotide reductase (RNR) from bacteriophage T4. The metal center is structurally related to the zinc ribbon motif and to rubredoxin and rubrerythrin. Mutant enzymes of the homologous RNR from Escherichia coli, in which the coordinating cysteines, conserved in almost all known class III RNR sequences, have been mutated into alanines, are shown to be inactive as the result of their inability to generate the catalytically essential glycyl radical. The possible roles of the metal center are discussed in relationship to the currently proposed reaction mechanism for generation of the glycyl radical in class III RNRs.  相似文献   
23.
目的:建立天麻片中天麻素的高效液相色谱含量测定方法.方法:C18色谱柱(4.6 mm× 150 mm,5μm),流动相:乙腈-0.05%磷酸溶液(3:97),流速:1.0 ml·min-1,检测波长:220 nm.结果:天麻素与样品中其他组分分离效果较好,天麻素在(0.0992~1.4880)μg范围内具有良好线性关系(r=0.9999),平均回收率为97.09%(RSD=0.47%.n=6).结论:采用此方法测定天麻片中天麻素的含量,准确可靠,简便易行.  相似文献   
24.
对特发性血小板减少性紫癜(ITP)患者60例子口服仙连颗粒,观测其血小板计教、骨髓巨核细胞及中医不同证型的疗效比较.结果发现,仙连颗粒能够提高血小板数量,改善巨核细胞成熟障碍,对阴虚血热型疗效较好,对血热妄行型疗效较差,对气虚不摄型的作用介于二型之间.  相似文献   
25.
Uncertainties about the use of inhaled nitric oxide in preterm infants   总被引:3,自引:0,他引:3  
Respiratory failure in the premature neonate is frequently complicated by pulmonary hypertension. When conventional therapies including administration of exogenous surfactant, conventional mechanical ventilation or high-frequency oscillatory ventilation using an appropriate high-volume strategy have failed, one should assess the pulmonary circulation status with colour-coded Doppler echocardiography. There is now considerable evidence that the regulation of foetal and postnatal pulmonary circulation occurs via nitric oxide (NO), and that persistent pulmonary hypertension of the neonate may be related to a relative deficiency in NO release. Low-dose (10-20 ppm), short-duration (1-2 d) inhaled NO has generally been shown to improve the oxygenation and relieve pulmonary hypertension in premature neonates with severely hypoxaemic respiratory failure. Whether this therapy (eventually prolonged >1-3 wk?) would improve survival and lessen morbidity (e.g. intracranial haemorrhage and chronic lung disease) remains to be proven by appropriately designed controlled trials. Until these issues can be clarified, NO therapy for premature neonates should be still considered as an experimental drug, and its use restricted to clinical studies.  相似文献   
26.
Stressful life events are frequently associated with outward signs of irritable bowel syndrome (IBS). Increasing evidence suggests that acute and chronic stress stimuli implicate different physiological mechanisms and neuroendocrine responses. Therefore, we investigated the influence of acute and chronic stress on visceral nociception in female rats and the involvement of colonic mast cells in this effect. The effect of acute and chronic partial restraint stress (PRS) on visceral sensitivity to rectal distension (RD) was assessed by abdominal muscle electromyography. Colonic mast cell activation was determined by measuring histamine release after in vitro stimulation with substance P (SP) in colonic samples from rats experiencing RD vs. controls. Acute PRS significantly enhanced abdominal response to RD compared with sham PRS for all volumes of distension. In contrast, chronic PRS induced a hyperalgesic response for the highest volumes of distension (0.8 and 1.2 mL), but did not affect the number of abdominal contractions for the lowest volume (0.4 mL) compared with controls. Both acute and chronic PRS increased in vitro SP-induced histamine release without affecting mast cell numbers. RD induced similar in vitro histamine release from colonic samples from both acute and chronic PRS rats; this release, however, was significantly higher than that measured in sham-PRS rats. Acute and chronic PRS differently influence visceral sensitivity in response to RD in female rats. This difference, however, cannot be attributed to a different effect of either stress paradigm on mast cell histamine release.  相似文献   
27.

Background

Although active surveillance is increasingly used for the management of low-risk prostate cancer, many eligible patients are still nonetheless subject to curative treatment. One argument for considering surgery rather than active surveillance is that the probability of postoperative recovery of erectile function is age dependent, that is, patients who delay surgery may lose the window of opportunity to recover erectile function after surgery.

Objective

To model erectile function over a 10-yr period for immediate surgery versus active surveillance.

Design, setting, and participants

Data from 1103 men who underwent radical prostatectomy at a tertiary referral center were used.

Outcome measurements and statistical analysis

Patients completed the International Index of Erectile Function (IIEF-6) pre- and postoperatively as a routine part of clinical care. Preoperative IIEF-6 scores were plotted against age to assess the natural rate of functional decline due to aging. Reported erectile scores in the 2-yr period following surgery were used to assess post-surgical recovery.

Results and limitations

Each year increase in patient age resulted in a 0.27 reduction in IIEF scores. In addition to IIEF reducing with increased age, the amount of erectile function that is recovered from presurgery to 12-mo postsurgery also decreases (?0.16 IIF points/yr, 95% confidence interval ?0.27, ?0.05, p = 0.006). However, delayed radical prostatectomy increased the mean IIEF-6 score over a 10-yr period compared with immediate surgery (p = 0.001), even under the assumption that all men placed on active surveillance are treated within 5 yr.

Conclusions

Small differences in erectile function recovery in younger men are offset by a longer period of time living with decreased postoperative function. Better erectile recovery in younger men should not be a factor used to recommend immediate surgery in patients suitable for active surveillance, even if crossover to surgery is predicted within a short period of time.

Patient summary

Younger men have better recovery of erectile function after surgery for prostate cancer. This has led to the suggestion that delaying surgery for low-risk disease may lead patients to miss a window of opportunity to recover erectile function postoperatively. We conducted a modeling study and found that predicted erectile recovery was far superior on delayed treatment because slightly better recovery in younger men is offset by a longer period of time living with poorer postoperative function in those choosing immediate surgery.  相似文献   
28.
In men who do not respond to initial radiation therapy, accurate knowledge of the site of cancer recurrence or persistence is necessary to understand treatment failure. We evaluated the pathologic characteristics of recurrent/persistent prostate cancer with tumor maps from the whole-mount slides of salvage radical prostatectomies performed between 2000 and 2014. Of 216 consecutive patients, detailed tumor maps were available for 77. Sixty-nine patients (90%) were found to have tumor in the apex, of which 46% occurred in the most apical 3 mm. Fifty-three patients (69%) had tumors at a distance of ≤5 mm from the urethra. Five patients had tumor directly involving the urethra, all of whom had urethral invasion at the apex. Seminal vesicle involvement was seen in 32 patients (42%), two of whom had tumor only in the seminal vesicles. Sixty-two patients (81%) had tumors in the distal apex, periurethral area, or seminal vesicles, that is, areas that are not routinely biopsied. Targeting these areas could improve the accuracy of biopsy when cancer recurrence is suspected.

Patient summary

When recurrence is suspected, clinicians should include biopsy of the distal apex, areas surrounding the urethra, and seminal vesicles. This information will help tailor successful salvage treatments.  相似文献   
29.
This study evaluates the effect of self-selected distracters (ie, bubbles, I Spy: Super Challenger book, music table, virtual reality glasses, or handheld video games) on pain, fear, and distress in 50 children and adolescents with cancer, ages 5 to 18, with port access or venipuncture. Using an intervention-comparison group design, participants were randomized to the comparison group (n = 28) to receive standard care or intervention group (n = 22) to receive distraction plus standard care. All participants rated their pain and fear, parents rated participant fear, and the nurse rated participant fear and distress at 3 points in time: before, during, and after port access or venipuncture. Results show that self-reported pain and fear were significantly correlated (P = .01) within treatment groups but not significantly different between groups. Intervention participants demonstrated significantly less fear (P <.001) and distress (P = .03) as rated by the nurse and approached significantly less fear (P = .07) as rated by the parent. All intervention parents said the needlestick was better because of the distracter. The authors conclude that distraction has the potential to reduce fear and distress during port access and venipuncture.  相似文献   
30.
目的评价癌症患者血中氧化应激标志物状况。方法测定111例癌症患者和36例健康对照血中丙二醛(MDA)和抗氧化标志物谷胱苷肽、谷胱苷肽过氧化物酶、黄嘌呤氧化酶、维生素E、维生素C及总抗氧化力浓度。结果癌症患者脂质过氧化产物MDA浓度明显高于健康对照(5.21±1.05nmol/L相对4.04±0.68nmol/L,P<0.001),而机体总抗氧化能力明显低于健康对照(4.39±0.98U/L相对5.78±0.93U/L,P<0.001),但内源性抗氧化标志物(谷胱苷肽、谷胱苷肽过氧化物酶、黄嘌呤氧化酶、维生素E和维生素C)无明显变化(P>0.05)。结论癌症患者体内脂质过氧化水平增高,总抗氧化能力下降。内源性抗氧化标志物谷胱苷肽、谷胱苷肽过氧化物酶、黄嘌呤氧化酶、维生素E和维生素C无明显变化。  相似文献   
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